High pressure pump



June 6, 1967 R, P. HEINTZ 3,323,467

HIGH PRESSURE PUMP Filed March 1 5, 1965 5 Sheets-Sheet l 32 3| 2,9 '.J) n A `54d 64 l GI FIG.:

INVENTOR.

RICHARD F. HEINTZ ATTORNEY June 6, 1967 R. RHEINTZ 3,323,467

HIGH PRES SURE PUMP 183 )f GO Filed March l5, 1965 5 Sheets-Sheet 2 loo '2' I l |23 g Q7."` IOS l5 1 94 9 'O5 ne FIG. 2 68 Q 23e f /245 1% o 242 28B 289 38o 2E-.v 1K/.N 263 :ai

y j 6 '4 28329'285 293 28| 282 FIG. 4

INVENTOR.

RICHARD P. HEINTZ ATTORNEY June 6, 1967 R. P. HEINTZ HIGH PRESSURE PUMP 25a l l 260e 24o 242 25 ,l A *f 252 26| 7" 244 L2G 255 239 249 24v 245 25:5V FIG. 3

INVENTOR.

RICHARD R HEINTz ATTORNEY United States Patent O 3,323,467 HIGH PRESSURE PUMP Richard P. Heintz, Kalamazoo, Mich., assignor to Pneumo Dynamics Corporation, Cleveland, Ohio, a corporation of Delaware Filed Mar. 15, 1965, Ser. No. 439,746 8 Claims. (Cl. 10S- 154) The present invention relates, as indicated, to a high pressure pump and, more particularly, to a pump of novel construction intended principally for operation in fuel injection systems and capable of producing unusually high pressures.

Presently available piston type pumps particularly designed for use in fuel injection systems have proved less than satisfactory for a number of reasons. Initially, they are designed to operate generally in the range of 4,000 to 6,000 p.s.i., which pressures do not actually provide optimum fuel combustion. At considerably higher pressures, there is a tendency for the wall of the surrounding sleeve or cylinder to expand with a resulting increase of fuel leakage along the clearance between the piston and the sleeve. In order to maintain such leakage at minimum values, manufacturing tolerances have necessarily been made exceedingly close, and this causes relatively high manufacturing costs. Such expansion of the sleeve also promotes clogging along the clearance area, with the expansion being greatest in the area immediately adjacent the pumping chamber and impurities tending to collect in the upper regions of the `clearance area.

With the above in mind, an object of the present invention is to provide a pump operable at comparatively high pressures 'while avoiding the excessive leakage Which would result in conventional structures under like pressure conditions. Moreover, the new pump does not rely on the usual close tolerances as noted and, in fact, the manufacturing tolerances of the sleeve and piston can actually be increased as compared with present pump designs.

A more specific object of the present invention is to reduce such leakage by providing an annular chamber in the outer periphery of the sleeve about the piston communicative with t-he pumping chamber in order that fluid at the pump pressure enters such annular chamber and subjects the sleeve to radially inward force effective to reduce the sleeve inner diameter and thus the clearance with the piston in that portion of the assembly inward of such annular chamber.

A further object of the present invention is to substantially prevent clogging due to impurities entering the clearance by virtue of providing pressurization of the outer periphery of the sleeve as noted above at a particular location in the assembly which relates the sleeve compression or internal reduction to the end portion of the piston. As a res-ult of such localized clearance reduction, any impurities which can pass beyond the piston end can freely proceed along the more remote and less restricted clearance of the parts for ultimate porting or discharge.

A further object of the present invention is to provide a pump adapted to operate at high pressures constructed vand arranged to hold dead volume in the pumping charnber to an absolute minimum and thereby increase the efficiency of the pump.

A further object of the invention is to provide in one form thereof a pump that is self-charging, that is, a charging pressure is built up within the pump itself sufficient to open the inlet valving to the pumping chamber.

A further object of the present invention is to provide a pump designed for operation at pressures generally in the range of from 10,000 to 40,000 p.s.i. or even higher, in a highly efficient manner and which can be manufactured at relatively low cost.

ICC

Other objects and advantages of the present invention will become apparent as the following description proceeds.

To the accomplishment of the foregoing and related ends, the invention, then, comprises the features hereinafter fully described and particularly pointed out in the claims, the following description and the annexed drawings setting forth in detail certain illustrative embodiments of the invention, these being indicative, however, of but a few of the various ways in which the principle of the invention may be employed.

In said annexed drawings:

FIG. l is a longitudinal sectional view through one form of high pressure pump constructed in accordance with the present invention;

FIG. 2 is a fragmentary, enlarged view of the pump of FIG. l, showing in more detail the pumping chamber and inlet and outlet valving mechanisms associated therewith;

FIG. 3 is a longitudinal sectional view through a modified form of pump constructed in accordance with the present invention; and

FIG. 4 is a fragmentary, enlarged view of the FIG. 3 pump form, showing in more detail the pumping charnber, the inlet and outlet valving mechanisms, and the manner in which the pressurized iiuid is delivered to the pumping chamber.

Referring now in more detail to the drawings, wherein like parts are indicated -by like reference numerals, and initially to the form of the invention illustrated in FIGS. 1 and 2, the pump comprises a generally cylindrical main housing 10 having a neck-like bottom extension portion 11. A front bearing retaining plate 12 is mounted on the housing 10 by means of a plurality of mounting bolts 13, with packing 14 being disposed in a groove formed in the bearing retaining plate 12 for sealing the mounting. A rear bearing retaining plate 15 is mounted on the pump housing 10 at the opposite side thereof by means of a plurality of mounting bolts 16, with packing 17 being similarly provided to seal the mounting. The rear bearing retaining plate 15 includes a mounting flange portion 18 provided with apertures (not shown) by means of which the pump can be operatively mounted.

Front and rear ball bearing members 19 and 20, respectively, are mounted, preferably by press-fitting, in annular openings provided therefor in the front and rear bearing retaining plates 12 and 15. An encased seal member 21 is similarly press fitted in an opening in the front bearing retaining plate 12 forwardly of the ball bearing member 19. n

A crankshaft generally indicated at 22 is rotatably mounted in the main housing, with the crankshaft being formed with axially spaced diametrical sections 23 and 24 which are preferably press-fitted in the inner race members of the -ball bearings 19 and 20. The crankshaft 22 further includes a diametrically reduced section 25 which extends through the seal 21, a further diametrically reduced section 26, and a forward reduced end portion 27. The axial section 26 is adapted to receive a V-groove belt pulley 28, with the latter being keyed to the crankshaft as indicated at 29 to establish the drive connection. The pulley 28 is retained on the crankshaft by means of a hex nut 30 and a washer 31, with the forward end portion 27 of the crankshaft being externally threaded for receiving the nut 30. The forward end portion 27 is additionally `diametrically bored, as is the nut 30, to receive a cotter pin 32. The pulley 28 is driven from a conventional power source in a well-known manner. It will be understood that the crankshaft could alternatively be driven by other sources of power as Well.

A filler plug 33 is mounted in an opening provided therefor in the top of the housing 10 for filling the inteaaa-sae? rior of the pump housing with a suitable lubricant. A series of passages commonly designated at 34 are formed in the rear bearing retaining plate to provide circulation between the housing chamber 35 and a reservoir or chamber provided by the recess 35a of the plate 15 when the latter is mounted and sealed on a mounting surface by means of the mounting flange 1S. The lubricant can thus ow freely through the bearing 2t) for lubricating the same. For shipping pur-poses, a shipping plug 36 is disposed in an annular recess 34a formed in the plate 15 and a shipping plate 37 is mounted on the bearing retaining plate 15 by bolts 38. An `O-ring 39 is provided disposed in a groove formed in the shipping plate 37 to seal the mounting of the plate. The shipping plug 36, shipping plate 37 and O-ring 39 are of course removed prior to installation of the pump.

The crankshaft 22 further includes a main, diametrically enlarged section 49 disposed generally centrally between the adjacent faces of the bearing retaining members 12 and 15. The axis of the cylindrical crank section 40 of the crankshaft is radially offset from the axis through the remaining sections 23-27 of the crankshaft thereby to provide the crank action necessary for reciprocation of the pump piston, the details of which will be hereinafter described. A cylindrical roller bearing 41 is mounted on the crank section 40 of the crankshaft, prefera-bly through a press-fitting of the inner race of the roller bearing on the periphery of such section. A bearing rim member 42 is mounted on the periphery of the outer race member of the bearing 41.

The bearing rim 42 is provided with an extension 43 provided with a radial opening 44 adapted to receive the upper end 45 of a tappet member 46. The tappet is pinned to the extension 43 by pin 47 which extends through aligned openings formed in the members, with the pin being retained in :place by retaining screws commonly designated at 48 which are received in threaded openings formed in the extension 43.

In the invention thus far described, then, it will be apparent that rotation of the crankshaft 22 by means of the pulley 28 will eifect reciprocation of the tappet 46 by virtue of the eccentric mounting of the crank section 40 of the crankshaft. To offset the rotative imbalance resulting from rotation of the crank section 4d of the crankshaft, counterbalance plates 49 and 50 are provided, which plates additionally serve to properly position the crankshaft during installation thereof. Each counterbalance plate 49 and 5t) is provided with stepped central openings 51 and 52, respectively, for receiving the crank section 40 and the adjacent, relatively reduced sections 23 and 24, respectively, of the crankshaft.

Shimming washers commonly designated at 53 are provided as required between the 4bearing retaining plates 12 and 15 and the counterbalance plates 49 and 50 for spacing the plates 49 and S0 and thus the crank section 40 of the crankshaft in the proper position in the housing.

A connecting rod comprising upper and lower rod sections 54 and 55 is operatively connected to the tappet 46, with a connecting pin 56 extending through aligned openings formed in the upper rod section 54 and the upper section 45 of the tappet. A ball joint 57 connects the upper and lower sections 54 and 55 of the connecting rod to avoid side loading. The upper section 45 of the tappet 'is provided with a plurality of openings 58 for permitting lubricating duid to enter the interior of the tappet for lubricating the ball joint connection.

A piston housing 60 is mounted to the lower extension 11 of the pump housing 10, with the piston housing being provided with a flange 61 through which a plurality of mounting bolts commonly designa-ted at 62 extend into threaded engagement with openings provided therefor in the housing extension. Shimming washers cornmonly designated at 63 are provided as required for spacing the piston housing 60 from the housing extension 11 to properly position the pump piston in the piston sleeve. A packing member 64 is mounted in a groove formed in the housing extension 11 for sealing the connection between the piston and pump housings.

The piston housing 60 is internally bored to receive a piston sleeve 65, with the latter being preferably rounted within the piston housing bore by shrink-tting to provide a rigid connection adapted to sustain pressures in excess of those encountered during operation of the pump. To position the piston sleeve 65 within the pump housing bore, the latter is provided with -a shoulder or ledge portion 66 approximately intermediate Athe longitudinal dimension of the pump housing, and the piston sleeve is formed with a laterally enlarged lower flange portion 67 adapted to tightly engage the ledge 66 during assembling of the piston sleeve.

A poppet seat member 68 is mounted within the piston housing bore below the piston sleeve and packed as indicated at 69. The bottom end of the pump housing bore is internally threaded as indicated at 70 for receiving an inlet adapter 71, the leading end of which engages the bottom of the seat member 68 when the adapter is threaded in place. A lock nut 72 is provided for maintaining the adapter in its mounted position in the pump housing. The adapter 71 is internally threaded at its outer end as indicated at 73 for receiving a union fitting 74, with the latter being provided with an exposed, externally threaded portion 75 for receiving a coupling of the like (not shown)` communicative with a source of uid supply (not shown). The opposite end 76 of the -tting 74 is -generally frus-to-conical in shape and packing members 77an-d 78 are provided for sealing the mounting of the tting.

The pump piston 80 is mounted for reciprocation in the piston sleeve 65, with the upper end `of the piston S0 being in the form of a ball connecting portion 81 secured to the lower section 55 of the connecting rod. As best shown in FIG. 2, the piston 80 is provided with a flat bottom surface 82 which forms With the periphery of the piston -a rather sharp annular edge 83. The piston 80 is shown in FIG. 2 in its bottom position, and in such position the bottom face 82 is spaced closely adjacent the top of inlet poppet member 84. The latter is formed with a frusto-conical upper end portion 85 adapted to seat on annular edge 86 formed at the top of the sea-t member 68. The inle-t poppet 84 further includes a central spider portion S7 for mounting the poppet in the bore 88 of the seat member, and a bottom shaft-like portion 89. The latter 89 is provided with a retaining ring 90 for mounting a spring retaining member 91, with the latter receiving the bottom convolution of a helical compression spring 92. The upper convolution of spring 92 seats on an annular Shoulder 93 formed in the seat member 68. The compression spring 92 functions in the usual manner to bias the inlet poppet 84 to a closed position. During the charging of the pumping chamber, the spring 92 is compressed under the charging pressure of the fuel entering the pump through the inlet end thereof thereby unseating the poppet from the annular seat 86 to permit entry of the fuel into the pumping chamber.

The end of the piston 80 adjacent the pumping chamber is provided with a series of relatively small, axially spaced annular grooves commonly designated at 94, which grooves permit better equalization `of the pressure along the clearance area between the piston periphery and the bore of the piston sleeve 65 during the pumping stroke. The dotted line 95 indicates the position of the bottom face 82 of the piston when the piston is in its top position.

An outlet poppet housing 96 is mounted at one side of the piston housing 60 and is provided with a relatively reduced, externally threaded leading end portion 97 adapted to be threadedly received in an opening provided therefor in the piston housing 60. An intermediate section 98 of the outlet poppet housing is disposed within a. cylindrical extension portion 99 of the piston housing 68, with an annular packing member 100 being disposed in a -groove formed in the intermediate portion 98 to seal the mounting.

An outlet poppet 101 is m-ounted for movement within bore 102 formed in the poppet housing 96, with the forward, frusto-conical end 103 of the poppet being adapted to seat on an annular edge 104 of outlet poppet seat mem- 'fber 105. T-he opposite end 106 of the poppet 101 is radially reduced to receive a helical compression spring 107 which biases the poppet to a closed position. A seal 108 is provided disposed in an annular groove formed in the front face of the forward portion 97 of the poppet housing thereby to seal the mounting of the poppet seat member 105, which is preferably press-fitted in the bore 102 of the poppet housing.

The poppet 101 is provided with an axial passage 109, and a plurality of radial openings commonly designated-at 110 provide communication between the opening 109 and an annular -area 111 defined by the outer periphery of the forward portion 103 of the poppet and the bore 102 formed in the poppet housing. During the pumping stroke, the fuel at the relatively high pressures indicated will force the poppet 101 to an open position away from the seat S thereby permitting fuel to flow radially laround the forward end 103 of the poppet, into the thus expanded annular area 111 and through the radial openings 110 to the axial passage 109.

The outlet poppet `housing 96 is internally bored as indicated at 112 `adjacent the outer end thereof for receiving a suitable tting (not shown) for delivering the fuel directed through passage 109 to suitable control means forming part of the fuel injection system, for example, a fuel control valve or the like.

The periphery of the piston sleeve 65 in 4the area thereof generally outwardly from the piston or pumping -chamber 114 is formed with an annular chamber 115 the lower portion of which extends below the outlet passage 116 lea-ding from the pumping chamber 114. The passage 116 in turn communicates with a generally funnel-shaped opening 117 formed in the piston housing 60 communicative with the opening in the poppet seat member 105. During the pumping stroke, fuel Vunder pressure enters chamber 115 from the outlet passage 116 thereby pressurizing the outer periphery of the sleeve 65, the signiicance of which will be pointed out hereinbelow. The extending of a portion of the chamber 115 below the passage 116 reduces any tendency of the sleeve 65 to warp. The grooves 94 formed in the `outer lperiphery of the piston function to equalize the pressure along the clearance area generally opposite the chamber 114.

Referring back to FIG. l, the piston sleeve 65 is provided With a plurality of radial passages commonly designated at 118 the opposed ends of which communicate respectively with an inner annular groove 119 and an outer, relatively larger annular groove 120 formed in the inner and outer peripheries, respectively, of the piston sleeve. The annular passage 120 in turn communicates with passage 121 formed in the piston housing 60. Any fuel leakage along the clearance area between the piston 80' and the bore of the piston sleeve 65 will thus be discharged to the passage 121. The latter communicates at its outer end with an annular area 122 partially defined by the leading end -of the intermediate section 9S of the outlet poppet housing 96. An axial passage 123 formed in the outlet poppet housing 96 communicates with means (not shown) for returning the fuel to the fuel supply.

The poppet seat 68 is similarly formed with an annular passage 124 in the outer periphery thereof which communicates with passage 125 formed in the piston housing 60. In this manner any fuel leakage to the interface between the seat member 68 and the piston housing will be discharged through the passage 125 to the axial passage 123 and back to the fuel supply.

The operation of the pump illustrated in FIGS. l and 2 of the invention should be apparent from the above description. Fuel enters the pump through the inlet fitting 74, flowing axially through the adapter 71 and the poppet seat member 63. In the FIGS. l and 2 position, the piston is bottomed and the inlet poppet 84 is accordingly closed, preventing fuel from passing into the pumping chamber. The piston S0 in such bottom position at the end of the power stroke is spaced closely adjacent the top of the poppet 84, which results in a relatively small dead space. As the piston 30 moves upwardly, as controlled by the crankshaft rotation, the pumping chamber 114 as it expands is at a relatively low pressure and the charging pressure of the fuel entering the pump is sucient to move the end of the poppet from seat 86 simultaneously compressing the spring 92, to permit flow of fuel into the pumping chamber. The pumping chamber continues to expand until the bottom 82 of the piston reaches the dotted line position indicated at at the top of the stroke. The outlet poppet spring of course pre- During the pumping stroke, f-uel pumped from thev pumping chamber through the passage 116 enters the annular chamber formed in the outer periphery of the piston sleeve 65. There is thus created a pressure force acting on the outer periphery of the piston sleeve greater than` Athe pressure in the pumping chamber acting on the inner periphery of the sleeve because of the respective differential areas. The piston sleeve, in the portion thereof adjacent the chamber 114, is consequently slightly compressed inwardly thereby reducing the inside diameter of the piston sleeve and thus the clearance between the sleeve and the piston.

The importance of pressurizing the outer periphery of the piston sleeve 65 can best be realized by further reference t-o present pump constructions, the disadvantages of which were briey noted above. In pumps operating at any pressure, the clearance between the piston and the piston sleeve has to be made quite small to reduce to the extent possible leakage along the clearance area. A clearance of .0001 vis consequently common and adds substantially to the machining costs of the pump. During operation, pressures in the pumping chamber expand the clearance between the piston and the sleeve, as explained, with s-uch clearance commonly increasing to an unsatisfactorily large .0004" at 20,000 p.s.i. which results in -increased leakage. Moreover, the expansion is not uniform along the clearance area with the greater degree of expansion being adjacent the piston chamber. There is thus formed an upwardly converging clearance opening, the relatively enlarged bottom portion of which 4is. capable of receiving relatively large impurity particles which, because of their size, cannot be passed along the entire clearance area, which is relatively smaller at its upper end. As a result, impurity clogging is a significant factor in present pump constructions.

By means of the present invention, the problems of leakage and clogging are substantially eliminated. By pressurizing the outer periphery of the piston sleeve, expansion of the clearance area is not only eliminated, but the clearance is actually reduced in the area thereof adjacent the piston chamber. The significance of clearance reduction in such area is two-fold. Initially, there is no tendency for clogging of particles along the clearance area. Any particles passing the relatively reduced clearance area adjacent the pumping chamber Will automatically pass upwardly along the relatively larger clearance area for subsequent discharge through the radial passages 118 formed in the piston sleeve to the passage 121. Secondly, by reducing during operation the clearance area adjacent the piston chamber, which area, as will be understood, controls the leakage along the interface, a substantially larger clearance can be initially provided thereby considerably reducing the tolerance requirements. A clearance in the range of .0002-.0O025" has proven very satisfactory and has greatly reduced machining costs. By overcoming the problems of leakage and clogging, the pump of the present invention is capable yof fuel delivery at the indicated, substantially higher pressures thereby enhancing fuel combustion.

It should also be noted that the piston and inlet poppet valve arrangement of the present invention has reduced the piston chamber dead space to a minimum. The bottom fiat face of the piston at the bottom of the pumping stroke is closely adjacent the top of the inlet poppet 04 thereby greatly reducing the unswept volume of the chamber, which is of the utmost importance in pumps designed to operate at relatively high pressures. The outlet poppet valve 101 is similarly positioned relatively adjacent the pumping chamber so as to reduce the volume pressurized during the pumping stroke to a minimum. The valving arrangement permits crankshaft speeds up to 6,000 revolutions per minute, significantly higher than present pump designs.

There is shown in FIGS. 3 and 4 a modified form of pump construction. In this form the pump housing 200 is provided with a hub portion 201 within which is rotatably mounted a crank shaft generally indicated at 202, with a crankshaft bearing 203 being disposed within the hub for rotatably mounting the crankshaft. The crankshaft further includes an intermediate reduced Section 204 which extends through an end opening 205 in the .pump housing, with such opening being sealed by means of an encased sealing member 206. A further reduced crankshaft section 207 mounts a V-grooved belt pulley 208 by keying means 209 in the same manner as previously described. The outer end 210 of the crankshaft is externally threaded for receiving nut 211, with a washer 212 and a cotter pin 213 completing the crankshaft mounting.

A crank member 214 of generally cup-like configuration is mounted on the end of the main section 21S of the crankshaft by means of a plurality of mounting bolts 216, only one of which is illustrated in FIG. 3, with thrust washers 216a Ibeing positioned around the crankshaft and between the member 214 and the end of the hub 201. A connecting rod cylinder 217 is telescopically mounted on the crank member 214 adjacent the open end thereof, with a connecting rod bearing 218 being mounted within the cylinder 217 for rotatably mounting the crank member 214. It will be noted that the crankshaft and connecting rod bearings are in nested arrangement so that only two bearings are required to rotatably mount the crankshaft and connecting rod cylinder.

The axis of the crank member 214 mounted within the cylinder 217 is radially offset relative to the axis of the crankshaft 202 thereby to provide the desired crank action for reciprocating connecting rod 219, the upper end of which is threadedly received in a tapped opening in the cylinder 217. A retainer plate 220 is mounted on the pump housing 200 `by bolts 221 to enclose the open end of the same.

In the FIGS. 3-4 form of the invention, fuel charging pressure sufficient to open the inlet poppet valve is built up within the pump itself by centrifugal force. Fuel is delivered to the upper portion of the pump housing through a fuel supply line 222, with the latter mounting at its leading end a fitting 223 mounted in a threaded opening in the pump housing. A passage 224 is provided in the pump housing for delivering the 4fuel to an annular chamber 225 defined by the periphery of the section 204` of the crankshaft and the inner periphery of the hub portion 201 of the pump housing. Fuel is delivered from the annular chamber 225 through a plurality of radial passages commonly designated at 226 to an axial passage 227 formed in the main section 215 of the crankshaft. The axial passage 227 communicates at the opposite end thereof with a plurality of relatively longer radial passages cornmonly designated at 223 formed in the base of the crank member 214, with such radial passages at their outer ends communicating with the pump housing chamber 229. The bottom of the chamber 229 openly communicates with an annular chamber 230 surrounding the connecting rod 219. A plug 231 caps the end of the passage 227.

It will thus be seen that fuel directed to the pump through supply line 222 passes through the axial passage 227 of the crankshaft and outwardly through the radial passages 22S formed in the crank member 214 into the chamber 229. The fuel is thus subjected to considerable centrifugal force during crankshaft rotation thereby building up a charging pressure within the chamber 229. By way of example, the charging pressure of the fuel within the chamber 229 is normally around p.s.i., substantially in excess of the pressure required to open the inlet poppet valve for fuel delivery to the pumping chamber.

The bottom of the pump housing 200 is provided with a ange 232 adapted to receive a complementary flange 233 formed at the top of piston housing 234, lwith a plurality of mounting bolts 235, only one of which is shown in FIG. 3, being provided to secure such mounting. Shimming washers commonly designated at 236 are provided as required to space the flanges 232 and 233 to properly position the pump piston. An annular packing member 237 is provided to seal the connection.

The piston housing 234 is formed with passages 238 and 239 for delivering fuel under charging pressure to the inlet poppet side of the pump. The adjacent ends of the passages 23S and 239 communicate with an annular chamber 240 one end of which is defined -by an annular shoulder 241 formed on outlet poppet housing 242.

In generally the sarne manner as described above, the piston housing 234 has mounted therein piston sleeve 243, inlet poppet seat -member 244 and an inlet adapter 245. There is additionally provided in this form a metering disk 246 which engages the 'bottom of the seat member 244 and provides a metering orifice 247 through which the fuel can be metered to the inlet poppet. The bottom of the bore in the piston housing 234 is internally threaded to receive the inlet adapter 245, with a lock nut 248 being provided to secure the same in place. The bottom of the metering disk 246 is provided with a plurality of grooves or passages 249 for directing fuel delivered to an annular passage 250 from the passage 239 to an inner annular chamber 251 below the bottom of the metering disk 246. A threaded metering control rod 252 is threadedly mounted for axial movement within the inlet adapter and is adapted to be connected at its lower end to a throttle control link 253. The top of the metering control rod 252 is conically shaped and is adapted to seat on the area of the metering disk 245 defining the metering orifice 247 there-by to close the same.

It will thus be apparent that the control rod 252 can be axially adjusted in the inlet adapter 245 `by the throttle control link 253 thereby to entirely close, as sho-wn in FIGS. 3 and 4, or adjustably open the metering orifice. The throttle control link 253 is provided with an opening 254 suitably connected to control means (not shown) by means of which the link 253 can be adjustalbly moved. Such control means may, for example, comprise 'a suitable linkage assembly connected to a throttle control positioned, e.g., in the cab of a vehicle.

Packing members 255, 256 and 257 are provided as illustrated for sealing the assembly.

The pump piston and inlet poppet valve in the FIGS. 3 4 form are generally similar in `construction and mounting to such members described above. The piston 258 is thus provided at its upper end with a ball connection 259 for operatively connecting the Ipiston to the connecting rod 219. The piston is provided adjacent its bottom end with -a plurality of relatively small .annular grooves 260, and an annular chamber 261m is formed in the periphery of the sleeve 243. The inlet poppet 261 lis mounted for movement within the upper cylindrical section 262 of the seat member 244, with the inlet poppet being provided with a top, conical portion 263 adapted to seat on the lannular rim or edge 264 of the seat member. A helical compression spring 265 is provided for biasing the poppet to a closed position and a spring retaining member 266 is mounted on the poppe-t adjacent the `bottom thereof.

The outlet poppet construction is similarly Substantially the same `as that `described above. As best shown in FIG. 4, the forward end 267 of the outlet poppet housing 242 is externally threaded for mounting in 4a threaded opening provided therefor in lthe piston housing, with a seal 267a being provided to seal such mounting. A poppet seat member 268 is disposed inwardly of the forward end 267 within the seal 267a and provides `an annular seat 269 adapted to .be contacted by the leading conical end portion 270 of the outlet poppet 271. The latter is diametrically reduced at the rear end thereof for receiving telescopically a helical compression spring 272 which biases the outlet poppet valve to a closed positon, The outlet poppet is formed with an axial fuel outlet passage 273.

A passage 274 is formed in the piston sleeve communieating with the pumping chamber 275, and an aligned passage 276 is formed in the piston housing 234. An annular chamber 277 surrounds the forward end of :the poppet 271, and a plurality of radial passages 278 are formed in such forward end of the poppet to provide communication with the axial passage 273. Fuel -is thus pumped from the pumping chamber 275 through the passages 274 and and 276 into contact with the forward conical end 267 of the poppet, thereby forcing the same rearwardly, compressing spring 272 and providing communication through thc chamber 277 and passages 278 to the axial passage 273.

An outlet adapter 280 is threadedly received in the outer end of the outlet poppet housing 242, with an annular packing mem-ber 281 being provided to seal such mounting. A sleeve 282 is mounted within the outlet adapter 280 and is adapted to receive a flexible, preferably metal tubing 4member 283 which extends to the leading end of the sleeve. The opposite end of the tubing 283 communicates with a control Valve (not shown) or the like downstream of the pump and forming no part of the present invention. In the form shown, a protective plastic casing or sheath 284 is mounted around and preferably secured to the leading, diametrically reduced end 285 of the sleeve 282 and serves to protect the tubing 283. The inner end 286 of the sleeve 282 is beveled as illustrated to tightly engage a complemental beveled surf-ace 287 formed in the outlet housing 242,

A longitudinal passage 288 is formed in the outlet housing 242 to provide for fuel leakage, with the outer end of the passage 288 communicating with an annular passage 289 surrounding the sleeve 282, .a plurality of radial passages commonly designated at 290 formed in the sleeve 282, and annular passage 291 surrounding the tubing 283. The passage 291 in turn communicates with the annular space 293 Ibetween the tubing 283 and the sheath 284 for returning minor fuel leakage to the fuel supply.

The operation of the pump illustra-ted in FIGS. 3 and 4 is similar to that previously described in the FIGS. 1-2 embodiment. In the FIGS. 3-4 embodiment, however, the fuel is pressurized within the pump housing itself by centrifugal action as described, with the fuel being delivered to the inlet poppet at approximately 130 p.s.i. Itwill be understood that the quantity of fuel ow from the pump is elfectively controlled by the positioning of the metering control rod 252, as controlled by the throttle control link 253. By regulating the spacing of the conical end of the control rod 252 from the metering orice 247, the amount of fuel delivered to the pumping chamber 275 can be effectively controlled, and the pump form of FIGS. 3-4 is thus of variable output, varying with the fuel charge delivered t-o the pumping chamber.

During the pumping stroke, fuel is received in the annular chamber 260a thereby pressurizing the outer periphery of the piston sleeve 243 to thus reduce clogging and leakage of fuel along .the clearance, as above explained. Further, in this form of the invention as well, the pumping chamber dead space has been reduced to a minimum by reducing the unswept volume in the pumping chamber.

Although both pump forms of the present invention are designed primarily for fuel injection systems, it will be apparent to those skilled in the art that the principles of the invention may have application in other environments as well, e.g. in hydraulic systems.

Other -modes of lapplying the principle of the invention may be employed, change being made as regards the details described, provided the features stated in any of the following claims or the equivalent of such be employed.

I therefore particularly point out and distinctly claim as my invention:

1. A high pressure pump comprising housing means, -crangshaft means rotatably mounted within said housing, said crankshaft means including a crank member mounted on said crankshaft and having a cylindrical end portion surrounding and spaced from said crankshaft, means for delivering uid to said housing, passage means formed in said crankshaft and said crank member, with the passages formed in said crank member extending radially relative to the axis thereof whereby fluid delivered to said housing is conveyed through said passages and radially outwardly under centrifugal force to a housing chamber radially outwardly of said crank member, piston sleeve means mounted in said housing, piston means operatively connected to said crank member and mounted for reciprocation within said piston sleeve, said piston sleeve and piston defining an expansible pumping chamber at one end of said piston, inlet valve means for delivering uid to said pumping lchamber outlet valve means for receiving iluid from said pumping chamber at relatively high pressures, and means internally of said pump for delivering uid from said housing chamber to said inlet valve means.

2. The combination of claim 1 wherein said means for delivering fliud from said housing chamber to said inlet valve means includes control means for metering fluid tlow to said inlet valve means.

3. The combination of claim 2 wherein said metering control means comprises a metering disk having a central orice therein and a metering valve movable axially toward and from such orifice thereby to control fuel flow through such orice to said inlet valve means.

4. The combination of claim 1 further including means for pressurizing the outer periphery of said piston sleeve in the area generally radially outwardly of said pumping chamber such pressurization reducing the clearance in such area, thereby reducing'leakage from the pumping chamber.

5. The combination of claim 4 wherein said means for pressurizing the outer periphery of said piston sleeve comprises an annular chamber at the outer periphery of said piston sleeve, one end of said chamber being approximately aligned with the bottom of said piston when the latter is in its top position.

6. The combination of claim 5 wherein said piston is provided with a plurality of annular, peripheral grooves adjacent the pumping end thereof to equalize the pressure along the clearance area between the piston and piston sleeve as such piston end during the pumping stroke.

7. A pump comprising housing means, crank means operatively mounted within said housing means, a piston sleeve mounted within said housing, a piston operatively connected to said crank means for reciprocation thereby and mounted within said piston sleeve for movement relative thereto, Isaid piston and piston sleeve dening an eX- pansible pumping chamber, a poppet seat member mounted partially within said piston sleeve, inlet poppet valve means mounted within said poppet seat member coaxial with said piston for `controlling the delivery of fuel to said pumping chamber and defining the bottom of said pumping chamber, adjustable inlet metering means for adjustably metering the flow of fuel to said inlet poppet valve means, spring' biased outlet poppet valve means communicating with said pumping chamber for receiving fluid therefrom, and an annular chamber at the exterior periphery of said sleeve between said sleeve and said housing generally radially outwardly of said pumping chamber, said pumping chamber directly radially communicating with said annular chamber and delivering fluid under pressure thereto during the entire pumping stroke for pressurizing the outer periphery of said piston sleeve thereby to prevent expansion of the bore wall of said'piston sleeve and leakage along the clearance area between said piston and said piston sleeve.

8. The combination of claim 7 wherein one end of said annular chamber is approximately aligned with the bottom of said piston when the latter is in its top position.

References Cited UNITED STATES PATENTS 2,604,855 7/1952 TOWler et a1. 103-153 3,016,717 7/1962 Gottzmanl'l 10B-153 3,077,899 2/1963 Waibel 137-512 3,128,941 4/1964 Waibel 103-153 3,186,167 6/1165 Chute 1113-5 DONLEY I. STOCKING, Primary Examiner.

20 HENRY F. RADUAZO, Examiner. 

1. A HIGH PRESSURE PUMP COMPRISING HOUSING MEANS, CRANKSHAFT MEANS ROTATABLY MOUNTED WITHIN SAID HOUSING, SAID CRANKSHAFT MEANS INCLUDING A CRANK MEMBER MOUNTED ON SAID CRANKSHAFT AND HAVING A CYLINDRICAL END PORTION SURROUNDING AND SPACED FROM SAID CRANKSHAFT, MEANS FOR DELIVERING FLUID TO SAID HOUSING, PASSAGE MEANS FORMED IN SAID CRANKSHAFT AND SAID CRANK MEMBER, WITH THE PASSAGES FORMED IN SAID CRANK MEMBER EXTENDING RADIALLY RELATIVE TO THE AXIS THEREOF WHEREBY FLUID DELIVERED TO SAID HOUSING IS CONVEYED THROUGH SAID PASSAGES AND RADIALLY OUTWARDLY UNDER CENTRIFUGAL FORCE TO A HOUSING CHAMBER RADIALLY OUTWARDLY OF SAID CRANK MEMBER, PISTON SLEEVE MEANS MOUNTED IN SAID HOUSING, PISTON MEANS OPERATIVELY CONNECTED TO SAID CRANK MEMBER AND MOUNTED FOR RECIPROCATION WITHIN SAID PISTON SLEEVE, SAID PISTON SLEEVE AND PISTON DEFINING AN EXPANSIBLE PUMPING CHAMBER AT ONE END OF SAID PISTON, INLET VALVE MEANS FOR DELIVERING FLUID TO SAID PUMPING CHAMBER OUTLET VALVE MEANS FOR RECEIVING FLUID FROM SAID PUMPING CHAMBER AT RELATIVELY HIGH PRESSURES, AND MEANS INTERNALLY OF SAID PUMP FOR DELIVERING FLUID FROM SAID HOUSING CHAMBER TO SAID INLET VALVE MEANS. 